Apparatus for perforating sheet material



July 3, 1934. 7 Q WALES 7 1,964,752

APPARATUS FOR PERFORATING SHEET MATERIAL Filed March 25, 1932 2 Sheets-Sheet 1 BY P M ATTORNEY 2 Sheet-Sheet 2 G. F. WALES APPARATUS FOR PERFORATING SHEET MATERIAL Filed March '25, 1932 l-lllll INVENTOR ATTORNEYS July 3, 1934.

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Patented July 3, 1934 UNITED STATES APPARATUS FOR ranroaa'rme smm'r MATERIAL George F. Wales, Kenmore, N. Y. Application March 25, 1932, Serial No. 601,201

\ 4 Claims. (01. 164-94) This invention relates to an apparatus for perforating sheet material such as sheet metal.

Perforating apparatus as heretofore constructed usually comprised a lower base or shoe 5 upon which was mounted a perforating die arid an upper head or holder upon which was mounted a punch cooperating with the die for producing holes in the sheet placed between the punch and die, said shoe and holder constituting the main elements of the frame of the hole punching apparatus. This die shoe was usually equipped with a plurality of upright guide pins of com-- paratively large size which engaged with holes in the punch holder. Thedie shoe was usually secured to the stationary bed of a punch press and the punch holder was rigidly mounted on the vertically movable ram or slide of the pres and moved by the same toward and from the die shoe, said guide pins maintaining the punch and die in alinement and ensuring proper cooperation of the same.

Obviously such an organization involves considerable difficulty in fastening the die shoe to the bed of the press and fastening the punch holder to the ram thereof in order to secure exact engagement of the punch and die and it therefore requires skillful and accurate work in fitting the guide pins and assembling the parts so that the same function properly.

One of the objects of this invention is to eliminate the work of mounting the die shoe and punch holder on the bed and ram of the press and also eliminating the guide pins heretoforerequired in this type of perforating apparatus.

Another object is to provide a frame in which the guide hole for a punch and the seat for a companion die may be bored in perfect alinement by single continuous boring operation.

Further objects of this invention are to so construct the mountings of the punch and die that the punch and die do not require fastening to the ram or slide and the bed, respectively, of the press but are merely placed freely between the ram and bed, also to so mount the die and the shoe that the die can be quickly removed from the shoe and restored thereto, and also to provide an improved combination of punch, stripping device and guiding means capable of quick and convenient removal from the holder and remounting thereon as a unit.

In the accompanying drawings:-

Figure 1 is a perspective view of a perforating apparatus, partly broken away, of one form of 55 perforating apparatus embodying my invention and showing the same provided with a plurality of perforating units.

Figure 2 is a similar view of a sheet of material perforated by the apparatus shown in Fig. 1.

Figure 3 is a fragmentary front elevation, partlyin section, and on an enlarged scale, of my improved perforating apparatus showing the position of the partsbefore the sheet to be punched or perforated is placed between the dies and punches of the perforating units thereof.

Figure 4 is a similar view showing the position of the parts when a sheet to, beperforated is placed between a die and the cooperating punch and associated parts. v

Figure 5 is a similarview showing the position of the parts when the punch has formed a hole in a sheet.

Figure 6 is a fragmentary sectional view of the press bed, die shoe and punch holder with the die and punch devices removed from these parts.

Figure 7 is a sectional view of the punching and stripping unit with the punch and the lower punch guide omitted. l V guiFigure 8 is a similar view of the lower punch 30 Figure 9 is a side view of the punch. v

Figure 10 is a bottom plan view of the punching and stripping unit. I 1

In the following description similar characters of reference indicate like parts in the several figures of the drawings.

The main frame or carrier of this punching apparatus may be of any suitable construction so that the workingparts mounted thereon may be supported on the stationary bed 20 of the press below the vertically movable rain or slide 21 of the latter and capable ofbeing, shifted freely over any desired part of the bed and still be underneath the ram for the purpose of opcrating the working parts of the punching apparatus to produce perforations in the sheet 22 which may be of any suitable material, e. g. sheet metal. Although the frame of the perforating apparatus may .bB-VBJIOIISIY constructed the same preferably comprises a lower supporting base or shoe which is adapted to rest on the press bed, and an upper head or holder which is mounted on top of the shoe. The base or shoe of the frame or carrier comprises a horizontal plate 23 of metal which is adapted to support the die members of a plurality of punch and die units and which is provided at suitable points 'withvdownwardly projecting legs 24 which rest upon the bed of the press. These legs are preferably constructed in the form of longitudinal flanges arranged at opposite longitudinal edges of the die plate 23 and also at different points on the underside of this plate intermediate of the longitudinal edges of the same, as shown in Fig. 1, so that the supporting shoe or base has the form of a bridge or arched span which rests at different points on the bed of the press, and is-thereby raised above the press bed '20 so as to form aclearance space 25 below the die supporting plate'which is adapted to receive the slugs which are punched out of the sheet material upon forming holes therein, and from which these slugs may be conveniently moved horizontallvfromthetopofthepress bedasthepunching operation progresses.

' The head or holder of the frame or carrier which is arranged above the baseor shoe has a horizontal plate 26 of metal which is provided at its oppomte longitudinal edges with legs 27 having the form of flanges resting 'on the longitudinal edge P rtions of the base plate 23 so that a gap 23 is formed between the lower base plate and the upper holder plate which extends fromthe front to the rear of the frame or carrlcr and into which the sheets of material to be perforated are introduced into. operative position relative to the several punch and die'units, and removed therefrom after the holes have been punched therein. a The lower shoe and upper holdor are rigidly but detachably connected with each other bymeans of a plurality of screws 29 passingfmm the upper holder into the lower shoe, and a plurality of dowels 30 arranged in corresponding openings 31, 32 in the holder and shoe, and dowels being preferably arranged within the longitudinal edge portions of the upper and lower plates and the legs formed on the respective parts of these plates, as shown' in Pig. 3.

i The lower shoe plate 33 is provided on its upper side with a plurality of upwardly opening sockets 38, each of which is axially in line with an opening 34 which extends from the lower end of the respective socket to the underside of the shoe plate 23 and forms an upwardly facing internal shoulder 35 at the bottom of this socket.

Within each socket is arranged alower 'die 36 having preferably the form of a cylindrical button which rests at its lower end on the bottom "shoulder 35 while its'top 37 is made of convex or upwardly tapering form and projects slightly above the upper side of the lower shoe plate 23. "Axially within each the upper to the lower end thereof is a die opendie 36 and extending from ing having an upper narrow part 38 and a lower downwardly widening part 39 which opens into the discharge passage 34. By extending this die button above the top of the shoe plate it is possible to grind ofl the upper end or-side of the die button for re-sharpening the same whenever this becomes necessary due to wear.

Vertically and axially in line with each of the die buttons and its socket 36 and discharge passage 34, a vertical guide opening 40 of cylindrical shape is formed in the adjacent part of the upper holder plate so as to extend from the upper to the underside of the latter. Within each of these guide openings 40 is arranged a punching a d stripping unit which is adapted to cooperate wi the die button below the same for the purpose of punching a hole in the sheet of material. Although this punching and stripping unit may be variously constructed that organization which is shown in the drawings is organized as follows:

noes-ass The numeral 41 represents a supporting sleeve which is arranged within the guide opening 40 and capable of sliding vertically freely therein. At its upper end this supporting sleeve is provided with an internal downwardly facing shoulder 42 and within the lower part thereof is arranged a supporting disk 43 which is connected at its periphery with the bore of the supporting sleeve by means of a screw joint 44. The underside of the supporting disk 43 and the lower end of the supporting sleeve 41 are rounded so as to form a convex spherical or ball-shaped surface 45 which is adapted to be engaged by the edge of the sheet of material which is to be perforated so that the whole punching unit is lifted by the wedging engagement of this sheet with said convex surface as the sheet is moved into its operative position between the respective die and punching unit.

Within the central part of each supporting disk 43 the same is provided with an upwardly tapering opening 46 which is axially in line with the corresponding die and is adapted to be engaged by the corresponding upwardly tapering periphery 47 of a guide bushing 48 which is held therein by a press fltdue to the locking taper on the cooperating surfaces on the periphery of this bushing and the bore of the opening 46. Within the center of the bushing 48 the same is provided with a guide opening 49 which is axially in line with the central opening of the die and which is adapted to receive the lower end portion or bit 49 of the body 50 of the punch. The bit end and body of the punch may be either of the same diameter or the bit may be of smaller diameter, in which latter case the junction of the bit and punch body is made in the form of a rounded fillet 51 and the upper end 52 of the guide opening 49 in the guide bushing 48 is made of corresponding rounded form so as to correspond to the fillet 51 and permit these parts to engage with each other if the punch should be driven down to the lowermost extremity of its stroke. At its upper end the punch body is provided with an enlarged head or anvil 53 which is adapted to be engaged by the ram or slide 21' of the press.

- In the preferred construction the junction of this anvil or head 53 and the body 50 of the punch is made in the form of a rounded fillet 54.

The numeral represents a follower which is of cylindrical tubular form and arranged between the upper part of the supporting sleeve 41 and the upper part of the punch body 50. At its upper end this follower engages with the underside of the head or anvil 53 of the punch and the upper end of the opening in this follower is rounded, as shown at 56, so as to fit the fillet 54 between the head and body of the punch. At its lower end the follower 55 is provided with an upwardly facing external shoulder 5'! which is adapted to engage with the downwardly facing shoulder 42 of the supporting sleeve 41, and thereby limit the upward movement of the followerin this supporting sleeve as well as that of the punch which is carried by this follower.

Within the supporting sleeve 41 and surrounding the central part of the punch is arranged a stripping or return spring 58 which is comparatively heavy and which bears with its lower end against the upper sideof the supporting disk 43, while its upper end bears against the underside of the follower 55, as shown in Figs. 3, 4, 5, and 7.

In assembling these parts the return or stripping spring is placed under an initial compression andthe supporting disk 43 is screwed into the lower end of the supporting sleeve for retaining the stripper spring within the supporting sleeve.

porting disk has been thus applied to the supporting sleeve these parts are preferably interlocked with each other by forming a punch mark or other deformation, such as peening one part over the other, across the screw joint between the same whereby unscrewing of this supporting disk from the supporting sleeve is prevented.

The numeral 59 represents a gage having preferably the form of a pin which is arranged across the rear part of the gap 28 in position to be engaged by the front edge of the sheet which is introduced between the lower shoe and the upper holder of the frame of the punching apparatus for the purpose of locating or registering the sheet to be perforated preparatory to punching holes therein.

In its preferred construction this gage pin is slidable vertically in the corresponding openings 60, 61 in the shoe plate 23 and in the holder plate 26, and is provided at its upper end with a knob or finger piece 62 whereby-the same may be removed out of the path of the sheet and permit the latter to be discharged from the rear end of the punching apparatus. It is thus possible for one operator to feed the sheets to be perforated to the perforating apparatus at the front side thereof while another operator removes the finished sheets from the rear side of this apparatus, thereby facilitating the punching operation and reducing the cost of this work. In order to permit the attendant on the front side of the perforating apparatus to conveniently introduce the sheets to be perforated into the proper position between .the several die and punch units, a clearance notch or space 63 is provided at one or more places in the front edge of the upper frame plate 26,.as shown for example at one place in Fig. 1, thereby enabling the operator at the front of the perforating device to reach with his hand in far enough between the lowerand upper frame plates to properly position the sheet to be perforated against the gage pin 59 and flanges 27 preparatory to operating the press for punching the holes in this sheet.

The operation of this perforating apparatus is as follows:

Assuming that combination punching and stripping units of the character described have been placed in the respective guide openings of the upper supporting plate or head 26 at the places where perforations are to be formed in the sheets of material, and that such punching and stripping units are omitted from such guide openings where no holes are to be formed in the sheet material, then the perforating apparatus is placed in the press with the lower shoe resting by its feet on the bed and its upper head or punch-holder arranged under the press ram, while the latter is in its elevated position. A sheet; of material is now fed by the operator into the gap between the lower and upper plates of the frame from the front end thereof until the advancing edge of this sheet engages with the gage 59 which has been so located that it will arrest the sheet in the proper position for forming the holes therein at. the desired locations.

Upon pushing the sheet into this gap of the frame the front edge of the sheet by engaging with the convex underside of the supporting disk 43 automatically raises the several punching and stripping units from the position in which each punching unit rests on the companion die 36 to an elevated position in which the die and lower end of the punching and stripping unit engage with the under side and upper side of the sheet, as shown in Fig. 4. This automatic adaptation of each punching and strippim; unit to the upper surface of the sheet of material is possible by reason of these units being free to float in their several guide openings in the upper frame plate without disturbing the relative position of the several members of each punching unit.

After the sheet has been thus placed in the gap of the frame and between the respective dies and punching and stripping units, the ram or slide of the press is lowered so that the latter engages the anvils or heads at the upper ends of the several punching and stripping units, whereby these punches are forced downwardly and the bits 49 at their lower ends are caused to penetrate the sheet of material and enter the opening in the respective dies, whereby each punch removes a slug or punching 65 of disk shape from the respective part of the sheet and forms a hole 66 in the latter, and drives the'punching into the opening of the die, as shown in Fig. 5. As these punches are successively moved downwardly in each die as the several punching operations succeed one another, the punchings are discharged from the center of the die and directed by the discharge opening 34 into the clearance space 25 below the intermediate part of the lower plate, and-the upper side of the bed from which the same are eventually removed by the operator.

In order to avoid undue strain on the punching apparatus the heads or anvils of the several punches are preferably so constructed that they are of different thicknesses or heights, as shown in Fig. 3, or the bodies and bits of the punches may be of different lengths so as to cause the several punches to engage the sheet to be perforated successively instead of simultaneously upon moving the ram downwardly upon the upper ends of the punches, thereby permitting a large number of openings to be produced in the sheet of material with the expenditure of a ccmparatively small amount of power and without straining any part of the punching apparatus or requiring the same to be made unduly heavy.

It is preferable to extend'the front edge of the lower base plate 23 a short distance forwardly of the front edge of the upper or head plate 26 so as to form an upwardly facing ledge 67 upon the base plate which will permit the operator to first rest the front edge of the sheet to be perforated on the base, and then push the same more conveniently and easily into the gap 28 between the upper and lower frame plates preparatory to performing the punching operation.

In order to enable the operator to push the sheet material fully into the gap between the intermediate part of the upper frame plate 26 and the intermediate part of the lower or base plate 23 and properly engage the advancing edge of this sheet with the gage 25 for locating the sheet with reference to the punching units the hand of the operator may grasp the sheet at its rear edge in line with one or another of the clearance spaces or notches 63 which are formed in the front edge of the upper frame plate.

LEO

One or another of these clearance spaces or notches 63 may also be employed for removing the sheet from the punching apparatus after the holes have been formed therein if it is desired to remove the sheet from the front side of the press or for pushing the sheet after the punching operation so that the same projects with its advancing edge from the rear side of the punching apparatus.

If desired similar notches 163 may be formed in the rear edge of the upper part 26 of the frame so as to permit the operator to reach into the gap 6'? far enough with his fingers and conveniently grasp the adjacent edge of the sheet for removing the same from the punching apparatus after the holes have been produced therein.

Removal of the perforated sheet from the rear side of the press is permitted by first lifting the gage 59 out of the path of the perforated sheet and then restoring this gage so that the same will be in a position to intercept the next following sheet and stop 'the same in the properly gaged position for producing the holes therein at the desired locations. By providing the frame with a longitudinal gap extending from the front to the rear end of the same the unperforated sheets may be fed into the perforating apparatus at the front end thereof by one operator and the finished sheets removed therefrom at the rear end of the apparatus, thereby enabling the operations of perforating sheets to be effected expeditiously and economically, this being an important item in producing a large number of sheets, having their perforations located in the same' places.

when the several punches are depressed by the ram of the press the follower of each punching and stripping unit moves down simultaneously with its companion punch whereby the stripping spring 58 is further compressed but the respective supporting disk 43 and the parts connected therewith remain at rest so that each follower 55 slides downwardly in the upper part of the respective supporting sleeve 41.

During the subsequent upward movement of the press ram each of the followers 55 is raised by the respective stripping spring 58 until the shoulder 57 of this follower engages with the shoulder 42 of the companion supporting sleeve, at which time the companion punch is also moved upwardly and the bit at its lower end is withdrawn from the hole which it has formed in the sheet material, and the lower end of the bit is flush with or slightly above the lower end of the bushing 48, as shown in Fig. 3. After the follower is arrested in its upward movement in the supporting sleeve 41 the ram '21 during its continued upward movement is disengaged from the upper end of the punch head and completes its upward stroke independently of the several punching devices into the position shown in Fig. 3.

By rendering the punching and stripping units removable from their guide openings in the upper frame plate independently of each other it is possible to utilize the same apparatus for punching holes in sheet material in differently spaced positions and different locations within the capacity of the apparatus.

It is also possible to vary the size of the perforations by selecting punches having bits and dies having the appropriate bores or central openings corresponding to the size of the holes which are required in any particular part of the sheets are to be perforated.

If it is desired to change the size or shape of the punch in the stripping and punching unit the latter is merely lifted out of the guide opening in the respective upper frame plate and replaced by another having a punch of the right size, or the withdrawn punching unit may have its punch and bushing 48 replaced by one of the desired size, it being understood that in all such interchanges the tubular die must also be changed in order to harmonize with the size of the punch which is adapted to cooperate therewith.

The removal of each die can be effected very easily by means of a tool which is inserted through the lower end of the discharge passage 34 which enables the die therein to be easily driven upwardly through the guide opening 40 of the upper frame plate when the respective punching and stripping unit is removed therefrom.

The guide 40 in the upper frame plate is of larger diameter and axially in line with the socket 33 which receives the tubular die and the discharge opening 34 which receives the punchings, thereby permitting these several openings to be produced by one continuous boring operation from the top of the upper frame plate downwardly through this plate and the lower frame plate, whereby absolute accuracy in the alinement of these several openings is assured and 105 permits of proper cooperation of each punch on the upper frame plate with the companion die button on the lower frame plate.

This form of'perforating apparatus permits of easily setting up the dies and punches for producing any particular punching operation on the sheet material while this apparatus is wholly removed from the power press, and after such setting up operation has been completed the perforating apparatus can be placed in any convenient position on the bed of the press and below the ram thereof for actuating the several punches by power to effect perforation of the sheets in accordance with the location of the holes as has been determined. Perforation of sheets can 20 therefore be effected expeditiously, accurately and economically and with the expenditure of a miniimum amount of power and labor and it is also possible to change the apparatus for producing perforations in different locations on'the sheets 125 and thus avoid the expense of a separate apparatus for each purpose.

I claim as my invention:-

1. A sheet material perforating apparatus adapted to be placed between the bed and ram 130 of a press, comprising a frame having a lower bridge shaped shoe having its opposite ends resting on said bed and its intermediate part elevated from the bed to form a clearance space 'therebetween, a head having the form of a bridge connected at its opposite ends with the opposite ends of said shoe and having its intermediate part separated from the shoe by a gap, and perforating devices mounted on said shoe and head and adapted to form holes in a sheet placed between said shoe and head upon moving said ram and bed one relatively to the other, each of said perforating devices comprising a lower die seated in a socket in the shoe, and a punching unit slidable vertically in a guide opening in said head and having a punch adapted to cooperate with said die, said socket being axially in line with and of smaller size than said guide opening.

2. A sheet material perforating apparatus adapted to be placed between the bed and ram of a press, comprising a framevv having a lower bridge shaped shoe having its opposite ends resting on said bed and its intermediate part elevated from the bed to form a clearance space therebetween, a head having the form of a bridge con-,- nected at its opposite ends with the opposite ends of said shoe and having its intermediate part separated from the shoe by a gap, and perforating devices mounted on said shoe and head and adapted to form holes in a sheet placed between said shoe and head upon moving said ram and bed one relatively to the other, each of said perforating devices comprising a lower die seated in a socket in the shoe, and a punching unit slidable vertically in a guide opening in said head and having a punch adapted to cooperate with said die, said socket being axially in line with and of a smaller size than said guide opening, and said shoe having a discharge passage from the lower end of said socket to the clearance space on the underside of said shoe.

3. A sheet material perforating apparatus comprising a frame having a lower shoe provided with a socket and an upper head provided with a guide opening arranged axially in line with said socket, a die arranged in said socket, and a punching unit arranged in said guide opening and including a supporting sleeve slidable lengthwise in said guide opening and provided at its upper end with an internal downwardly facing shoulder, a supporting disk secured to the lower end ofxsaid sleeve,

a tubular follower movable lengthwise in the upper part of said sleeve and having an upwardly facing external shoulder adapted to cooperate with the internal shoulder of said sleeve, a punch mo'mted on said follower and guided on said disk and adapted to cooperate with said die, and a spring interposed between said disk and fol- .lower.

facing external shoulder adapted to cooperate' with the internal shoulder of said sleeve, a punch mounted on said follower and adapted to cooperate with said die, a spring interposed between said disk and follower, said disk having an upwardly tapering bore, and a bushing having an upwardly tapering periphery engaging with said bore and provided with a central guide opening which receives said punch.

GEORGE F. WALES. 

